Author: freqlabs Date: Sat Oct 24 14:46:38 2020 New Revision: 367003 URL: https://svnweb.freebsd.org/changeset/base/367003
Log: kern_sysctl: Misc code cleanup Remove unused oidpp parameter from sysctl_sysctl_next_ls and add high level comments to describe how it works. No functional change. Reviewed by: imp MFC after: 1 week Sponsored by: iXsystems, Inc. Differential Revision: https://reviews.freebsd.org/D26854 Modified: head/sys/kern/kern_sysctl.c Modified: head/sys/kern/kern_sysctl.c ============================================================================== --- head/sys/kern/kern_sysctl.c Sat Oct 24 14:39:17 2020 (r367002) +++ head/sys/kern/kern_sysctl.c Sat Oct 24 14:46:38 2020 (r367003) @@ -1100,9 +1100,13 @@ sysctl_sysctl_name(SYSCTL_HANDLER_ARGS) static SYSCTL_NODE(_sysctl, CTL_SYSCTL_NAME, name, CTLFLAG_RD | CTLFLAG_MPSAFE | CTLFLAG_CAPRD, sysctl_sysctl_name, ""); +/* + * Walk the sysctl subtree at lsp until we find the given name, + * and return the next name in order by oid_number. + */ static int sysctl_sysctl_next_ls(struct sysctl_oid_list *lsp, int *name, u_int namelen, - int *next, int *len, int level, struct sysctl_oid **oidpp, bool honor_skip) + int *next, int *len, int level, bool honor_skip) { struct sysctl_oid *oidp; @@ -1110,7 +1114,6 @@ sysctl_sysctl_next_ls(struct sysctl_oid_list *lsp, int *len = level; SLIST_FOREACH(oidp, lsp, oid_link) { *next = oidp->oid_number; - *oidpp = oidp; if ((oidp->oid_kind & CTLFLAG_DORMANT) != 0) continue; @@ -1118,46 +1121,77 @@ sysctl_sysctl_next_ls(struct sysctl_oid_list *lsp, int if (honor_skip && (oidp->oid_kind & CTLFLAG_SKIP) != 0) continue; - if (!namelen) { + if (namelen == 0) { + /* + * We have reached a node with a full name match and are + * looking for the next oid in its children. + * + * For CTL_SYSCTL_NEXT we skip CTLTYPE_NODE (unless it + * has a handler) and move on to the children. + */ if ((oidp->oid_kind & CTLTYPE) != CTLTYPE_NODE) return (0); if (oidp->oid_handler) - /* We really should call the handler here...*/ return (0); lsp = SYSCTL_CHILDREN(oidp); - if (!sysctl_sysctl_next_ls(lsp, 0, 0, next+1, - len, level+1, oidpp, honor_skip)) + if (!sysctl_sysctl_next_ls(lsp, NULL, 0, next + 1, len, + level + 1, honor_skip)) return (0); + /* + * There were no useable children in this node. + * Continue searching for the next oid at this level. + */ goto emptynode; } + /* + * No match yet. Continue seeking the given name. + * + * We are iterating in order by oid_number, so skip oids lower + * than the one we are looking for. + * + * When the current oid_number is higher than the one we seek, + * that means we have reached the next oid in the sequence and + * should return it. + * + * If the oid_number matches the name at this level then we + * have to find a node to continue searching at the next level. + */ if (oidp->oid_number < *name) continue; - if (oidp->oid_number > *name) { + /* + * We have reached the next oid. + * + * For CTL_SYSCTL_NEXT we skip CTLTYPE_NODE (unless it + * has a handler) and move on to the children. + */ if ((oidp->oid_kind & CTLTYPE) != CTLTYPE_NODE) return (0); if (oidp->oid_handler) return (0); lsp = SYSCTL_CHILDREN(oidp); - if (!sysctl_sysctl_next_ls(lsp, name+1, namelen-1, - next+1, len, level+1, oidpp, honor_skip)) + if (!sysctl_sysctl_next_ls(lsp, name + 1, namelen - 1, + next + 1, len, level + 1, honor_skip)) return (0); goto next; } if ((oidp->oid_kind & CTLTYPE) != CTLTYPE_NODE) continue; - if (oidp->oid_handler) continue; - lsp = SYSCTL_CHILDREN(oidp); - if (!sysctl_sysctl_next_ls(lsp, name+1, namelen-1, next+1, - len, level+1, oidpp, honor_skip)) + if (!sysctl_sysctl_next_ls(lsp, name + 1, namelen - 1, + next + 1, len, level + 1, honor_skip)) return (0); next: + /* + * There were no useable children in this node. + * Continue searching for the next oid at the root level. + */ namelen = 1; emptynode: + /* Reset len in case a failed recursive call changed it. */ *len = level; } return (ENOENT); @@ -1169,13 +1203,12 @@ sysctl_sysctl_next(SYSCTL_HANDLER_ARGS) int *name = (int *) arg1; u_int namelen = arg2; int len, error; - struct sysctl_oid *oid; struct sysctl_oid_list *lsp = &sysctl__children; struct rm_priotracker tracker; int next[CTL_MAXNAME]; SYSCTL_RLOCK(&tracker); - error = sysctl_sysctl_next_ls(lsp, name, namelen, next, &len, 1, &oid, + error = sysctl_sysctl_next_ls(lsp, name, namelen, next, &len, 1, oidp->oid_number == CTL_SYSCTL_NEXT); SYSCTL_RUNLOCK(&tracker); if (error) _______________________________________________ svn-src-all@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/svn-src-all To unsubscribe, send any mail to "svn-src-all-unsubscr...@freebsd.org"
